基于裂隙网络渗流差异的消落带岩体劣化空间预测研究  

Spatial prediction method of rock mass deterioration in Drawdown zone based on seepage difference of fracture network

作　　者：白林丰 黄波林[1] 秦臻 秦盼盼 Bai Linfeng;Qin Panpan;Xu Kaikai(Hubei Key Laboratory of Disaster Prevention and Mitigation China Three Gorges University,Yichang 443002,China)

机构地区：[1]三峡大学防灾减灾湖北省重点实验室,湖北宜昌443002

出　　处：《灾害与防治工程》2021年第2期26-39,共14页Disaster and Control Engineering

基　　金：国家重点研发计划项目(2018YFC15048063);国家自然科学基金项目(42077234)。

摘　　要：三峡水库175m蓄水以来,水位周期性涨落,使得岸坡岩体强度下降而逐渐劣化,易导致岩质岸坡失稳破坏,因此引起了广泛的关注。岩体劣化与库水位的波动有关,其损伤劣化区域必然与水力调整范围有一定的关系。本文首次提出了基于裂隙网络模型渗流差异的岩体劣化空间分析方法。利用Beacher模型结合裂隙几何参数分布概型模拟岩体裂隙的空间分布,并基于裂隙截面面积相等,在裂隙网络中简化面状渗流为管道流,构建出裂隙网络渗流空间图。同时利用拓扑关系求解实际工况中岩体裂隙网络渗流空间的水头分布区域,通过不同水位下的渗流差异区域来推测可能发生岩体劣化的空间,得出存在水力差异的渗流相同区域、水位变动下新增的渗流区域两种情况都是预测的岩体劣化区域。这一预测方法将对三峡库区岩体劣化防治措施及防灾减灾有重要的指导意义。Since the 175m impoundment of the Three Gorges reservoir,the water level has fluctuated periodically,which makes the rock mass strength of the bank slope decline and gradually deteriorate,which is easy to lead to the instability and failure of the rock bank slope,so it has attracted extensive attention.The deterioration of rock mass is related to the fluctuation of reservoir water level,and its damage deterioration area must be related to the hydraulic adjustment range.In this paper,a spatial analysis method of rock mass deterioration based on seepage difference of fracture network model is proposed for the first time.The spatial distribution of rock mass fractures is simulated by using the beacher model combined with the distribution profile of fracture geometric parameters.Based on the equal fracture cross-sectional area,the planar seepage is simplified into pipeline flow in the fracture network,and the seepage spatial map of fracture network is constructed.At the same time,the topological relationship is used to solve the water head distribution area of the seepage space of the rock mass fracture network in the actual working condition.Through the seepage difference area under different water levels,the space where rock mass deterioration may occur is inferred.It is concluded that the same seepage area with hydraulic difference and the newly increased seepage area under water level change are the predicted rock mass deterioration areas.This prediction method will have important guiding significance for the prevention and control measures of rock mass deterioration and disaster prevention and reduction in the Three Gorges Reservoir area.

关 键 词：岩体劣化 三维离散裂隙网络 渗流差异 劣化空间 

分 类 号：TV6[水利工程—水利水电工程]